On Friday, January 24, 2014, Nima Arkani-Hamed of Institute for Advanced Study School of Natural Sciences will give his talk:
"Perturbative scattering amplitudes in gauge theories have remarkable simplicity and hidden infinite dimensional symmetries that are completely obscured in the conventional formulation of field theory using Feynman diagrams. This suggests the existence of a new understanding for scattering amplitudes where locality and unitarity do not play a central role but are derived consequences from a different starting point. In this talk I will present such an understanding for maximally supersymmetric scattering amplitudes in the planar limit, which are identified as ``the volume" of a new mathematical object--the Amplituhedron--generalizing the familiar notion of convex polygons into the (positive) Grassmannian. I will describe how locality and unitarity emerge hand-in-hand from positive geometry".